Infants and other incontinent individuals wear absorbent articles such as diapers to receive and contain urine and other body exudates. Absorbent articles function both to contain the discharged materials and to isolate these materials from the body of the wearer and from the wearer's garments and bed clothing.
Early prior art disposable diapers were generally flat composite sheets which were fitted to a baby in a flat state or incorporated geometric folding to achieve a suitable "baby shape." A major in-use problem with these prior art diapers is that gaps between the diaper and the baby's body tended to develop due to the semi-rigid nature of the absorbent body, especially after the diaper had been worn for a period of time. The gaps permitted leakage from the disposable diaper, thereby creating damp or wetted outer clothing and bedding around the baby.
One solution to the aforementioned problem is the use of elastics in the leg openings of the diaper to provide improved fit and containment characteristics. An example of such a prior art disposable diaper is disclosed in U.S. Pat. No. 3,860,003 issued to Buell on Jan. 14, 1975. While elasticized diapers such as those disclosed in Buell have achieved widespread acceptance and commercial success, the elasticized diapers still have a tendency to gap and therefore leak periodically.
A disposable diaper which conforms readily to the contours of the wearer's body offers many benefits including comfort, performance, containment and the like. By more readily conforming to the contours of the body the absorbent article employing the semi-elastic material of the present invention will fit more snugly, thereby reducing the likelihood of leakage of body exudates. Further, by conforming to the contours of the body, the absorbent article employing the three-dimensional substrate of the present invention will help reduce red marking of the skin by eliminating the need for excessive tensional forces used to shape the article.
The advantages of a three-dimensional article are provided by the incorporation of one or more formed substrates. Generally, such formed substrates comprise elongated zones which are incrementally stretched so as to increase their surface pathlength and boundary zones with shorter surface pathiengths disposed adjacent the elongated zone. The incrementally stretched elongated zone along with the boundary zones provides the substrate with a three-dimensional configuration without added forces or elastics. Thus, three-dimensional articles, as described herein, can be manufactured more quickly, easily and inexpensively than similar products currently in the market, thereby reducing their overall cost.
Thus, an object of the present invention is to provide an absorbent article comprising a formed substrate capable of assuming a macroscopic three-dimensional configuration.
Another object of the present invention to provide an absorbent article with a topsheet and/or backsheet comprising a formed substrate capable of assuming a macroscopic three-dimensional configuration in a relaxed condition.
Yet another object of the present invention to provide an absorbent article with a topsheet and/or backsheet comprising a formed substrate capable of assuming a macroscopic three-dimensional configuration in a relaxed condition without added elastics.
These and other objects of the present invention will be more readily apparent when considered in reference to the following description and when taken in conjunction with accompanying drawings.